NOVA SCOTIA NATURALLY: Rhodora’s spring colours

Rhodora on the fire barrens: A single cluster of flowers blossoms at the tip of an unbranched stem in this 2010 photo. (DAVID PATRIQUIN)

Rhododendrons and azaleas provide spectacular spring time blooms in the gardens of Nova Scotia but no more so than our native Rhododendron canadense in the countryside. Better known by its common name, rhodora, this deciduous woody shrub of the heath family (Ericaceae) begins to produce striking blooms of large purple-rose flowers before it leafs out. Flowers appear from early May to mid-June in exposed sites with wettish, acidic soils such as at the edges of bogs, in moist areas on rocky barrens, and forest swamps. Fly fishers say the first ones announce the emergence of mayfly and it’s time to catch trout.

Rhodora can occur as a few isolated plants among other shrubs or it can dominate an expanse of heathy shrubland. Huckleberry, blueberry and lambkill are common associated shrubs toward the dry end of rhodora’s spectrum and Labrador tea, leatherleaf, and sweet gale toward the wet end, with black spruce and shadbush often nearby.

The most spectacular blooms I have seen were on fire barrens on the Halifax south mainland. Several of these areas of granite outcrops and glacial erratics with jack pines and ericaceous shrubs burned in 2009, killing all above-ground vegetation. New shoots of rhodora sprouted in profusion from belowground stems in the wettish pockets and expanses within months of the fire.

In the spring of 2010, each of the still unbranched shoots produced a single but prominent cluster of flowers at its tip, creating a colourful contrast with the charred earth and tree trunks.

Just as pleasing to the senses is to come upon a stand of flowering rhodora in a wet clearing in a forest or alongside a boardwalk over a wet area. I have often stopped my car to admire a fringe of colour along the border of woods by the cleared right of way for a highway; in the spring such a sight can be little else but rhodora.

The beauty and setting of the rhodora flower were eulogized by no less than Ralph Waldo Emerson when he penned The Rhodora, in 1839. (see his poem in the box to the right)

Rhodora’s pleasures for the senses don’t end with the blooms; the leaves offer their own treats. The leaves (and rhodora’s genetic makeup) place rhodora among the deciduous azaleas (rhododendron section pentanthera), a group whose native species are concentrated in eastern North America. The leaves are relatively thin with prominent veins and have long whitish hairs pressed to the leaf. Leaves of our ornamental rhododendrons are evergreen, tend to be thick and leathery, lack hairs and many have scales on the undersides, never seen in azaleas.

As the season progresses, rhodora’s leaves become ever more fragrant. Don’t be tempted to make tea from them; they can be highly toxic! The leaves begin to change colour in late August. They are not particularly striking but there is a short window in late September/early October when they can go through a pastel pink stage before finally browning and dropping. It doesn’t happen in all places or years but it is well worth repeat visits to a rhodora shrubland to view this pastel landscape. Once the leaves fall, rhodora plants can still be recognized by their distinctive clusters of seed capsules or the husks that hang on well into the next spring.

How is this species doing? Distributed through eastern North America from Newfoundland to Ontario (but not in P.E.I.) and south to New Jersey and Pennsylvania, it is considered “secure” (conservation status S5) only in Atlantic Canada. Regardless, let’s never take this beauty for granted!